In pediatric shock, which of the following is a cause of obstructive shock?

Correct Answer: C

Rationale: Obstructive shock is caused by physical obstruction to blood flow. Severe aortic stenosis limits cardiac output, leading to inadequate systemic perfusion.

Correct Answer: A

Rationale: Preterm infants have underdeveloped lungs, and mechanical ventilation or high oxygen pressure can lead to alveolar rupture, causing air to accumulate in the pleural space (pneumothorax), leading to respiratory distress.

Correct Answer: C

Rationale: Smokeless tobacco use is strongly linked to cancers of the oral cavity and esophagus.

Correct Answer: B

Rationale: Anaphylactoid purpura (Henoch-Schanlein purpura) is the most common cause of non-thrombocytopenic purpura in children, characterized by a small-vessel vasculitis leading to purpuric rash, arthritis, and renal involvement.

Correct Answer: B

Rationale: Rheumatic polyarthritis predominantly affects large joints, not equally large and small joints.